I have an LG Neo Plasma & when I start the A/C it only cools for 10 seconds. I went outside to check outdoor unit & noticed that the fan was not moving. I checked the fan & it is not seized. Do I need a new fan as it is burnt out or a new card ??????

Make sure the setting on the remote is correct . Sun symbol for heating. Make sure the filters are clean. On heating, the indoor unit will 1/2 open the flap but the fan shouldn't start. The outdoor unit should start and if working properly, will be blowing cold air. The indoor unit will open the flap fully and the indoor fan will start once it gets hot then you should feel warm air. If the outdoor unit is blowing warmish air, I would say the reversing valve coil has failed or one of the indoor temp or pipe sensors are faulty. If a sensor fails, a "CH" error should appear on the display.

sounds like it's running backwards. possibly need a time delay in the condenser. make sure your drain line is clean.also inspect low voltage wires for bare/ chew spots near outdoor unit.

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Are you heating or cooling? When the outdoor unit shuts off how does it come back on. Or are you saying that the outdoor unit is short cycling off and on

Possibly a bad control board in the outdoor unit. Pull the disconnect outside to stop machine, wait 10 seconds and out back in. White mist was likely frost built up on indoor coil due to condenser running without the fan.

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Looks like a possible communication error. If you're willing I got one idea for ya. Turn power off to unit. The indoor and outdoor unit are connected and "communicate " through 4 wires, these are labeled 1,2,3,4. They should be color coded inside and out. Meaning if the color black is on 1 outside it should be on 1 inside. But, regardless, at the outside unit swap 1 and 4...2 and 3. Do the EXACT same thing at the inside unit. Then turn the power back on. I have ran into communication errors on mini splits simply because the "data" wire had a little nick or some kind of extra resistance that would throw a communication error but will work just fine as a supply voltage wire. Hope it fixes the problem. Good Luck!!

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I assume its the outside unit of the bedroom that freezes up ?? If the outdoor temperature is below 5 degrees celcuis, its likely to freeze up on the outdoor coil ( On heating mode), there is a defrost function which defrosts the machine automatically. If the indoor unit starts to freeze up ( on cooling mode), I would suggest that there is a shortage of refrigerant gas. Especially if the indoor unit starts to "spit" water out when it is running. There may be a gas leak due to a pipe failure or loose flared fitting. These must be rectified before recharging with gas.

It's communication error between indoor and out door.As you don't mention any error code, normal causes for your a/c problem may be one of this.
Comms Error, check your wiring, remove external pumps. Split/Multi - check volts from terminal N to 3 = 0 - 65 Vdc, Multi V - 4 Vdc terminals 3 and 4
or

Split = Outdoor unit fan problem. Check Outdoor fan motor is plugged in, Electrically & Mechanically sound, if not replace motor, otherwise replace PCB.

sounds like you have a bad coppressor

It sounds like you have a unit called a heat pump. When a heat pump unit is in cooling mode the outside unit blows hot air and the inside unit blows cold air. If the outside unit is blowing cold then the indoor unit is most likely blowing room temperature or warm air. It sounds like the thermostat could be controlling incorrectly or you could have a failed reversing valve which is the device that switches the unit from heating to cooling mode.